Abstract:A recent workshop on Gallium Nitride (GaN) semiconductor applications in Suzhou, China highlighted the rapid dynamics toward new market opportunities and Suzhou's efforts to grow the GaN ecosystem and drive these new industries.

January 16th, 2013

Developing GaN Ecosystems - From LEDs to Power Electronics

A recent workshop on Gallium Nitride (GaN) semiconductor applications in Suzhou highlighted the rapid dynamics toward new market opportunities and Suzhou's efforts to grow the GaN ecosystem and drive these new industries. It is rare that a material opens up new markets become a large market, like a silicon, but GaN, with unique properties to open up various new applications, has grown rapidly on the back of the LED industry.

A great deal of the world's LED manufacturing base has gone to China, which has had some over investment in recent years, leading to large GaN wafer capacity in China. With all that, GaN equipment, capacity and growth know-how, there is some movement to GaN power electronics, and lasers. Using the superior properties of GaN, power devices based on GaN are starting to appear in the market with the expectation that they will replace silicon power devices in some segments with their much lower power consumption.

~GaN Industry Alliance in Suzhou~The "Driving GaN Applications" Workshop in Suzhou on November 29th, brought together the whole GaN value chain, from research to device companies, new ventures and end-users to discuss these issues and opportunities. As was seen from the presentations, Suzhou has become a hub for joint GaN research and new ventures, and a key component is the Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), which also is the home to many nanotech spin-off companies.

It was described by Suzhou Nanotech Co. Ltd. that they are planning to further invest and grow the GaN ecosystem in Suzhou, in particular to new applications like power devices and lasers. Suzhou aims to fill-out the GaN value chain with a GaN industry alliance or consortium, bringing together domestic and worldwide companies, as well as attracting talent from worldwide. While Suzhou provides common platforms, as well as incentives and subsidies, it allows companies with world-class technologies and ideas to go rapidly from research to prototype, to a quick ramp-up to commercialization.

Suzhou has created a dynamic environment with many nanotech start-up companies in other applications, just with this kind of method of bringing together value chains and common platforms. During the Workshop roundtable discussions, the participants also reemphasized that such efforts are important for successful commercialization, such as connecting upstream and downstream players for collaboration and having an application development value chain. The participants also appreciated the role of SINANO as a collaboration platform, and its support of industry value chains.

Showing how much of a GaN hub Suzhou has become, AIXTRON, the global equipment company, that has sold many MOCVD systems to grow GaN wafers in China, has also established a training center in Suzhou to further the expertise in GaN growth and use.

~GaN Companies in China~A Suzhou company, Nanowin described how they are confident in driving down GaN costs, so that anyone who wants to use GaN in their application can use it. They use HVPE wafer growth using their own equipment, and have been doing good business selling their high-quality wafers for GaN lasers and lasers projectors. With SINANO, they will move to 6-inch wafers in 2013.

With Chinese worldwide, one of the latent strengths is that experts with global experience are coming back to Suzhou. One of those is Qian Sun, with experience at Yale and Bridgelux is now at Lattice Power as they drive GaN-on-silicon for LEDs. They have 6-inch wafers in research which is moving to mass production in 2013.

Another local Suhzou company with high-level talent is Dynax Semiconductor, the first commercial company in China to focus on GaN electronic device design and manufacturing. They explained how they can fill a niche for GaN RF chips for cellular base stations, as US companies have export restrictions for such devices. Communications companies are testing their devices now, and Dynax has also started on power devices. They said that GaN cost is not a problem. Dynax has developed 4GHz power transistors, power of 35W, efficiency. 50%, and gain 10dB, while their new product in development is at 2GHz, 120 W, efficiency 60%, and 10dB gain.

A related company, Suzhou Jiangzhan Semiconductor, wants to promote the development of the domestic Chinese GaN electronics industry by supplying local GaN epi-wafers. Suzhou Jiangzhan will produce GaN-on-SiC epi-wafers for high power microwave/RF amplifiers, and large size (6-8 inch) GaN-on-Si epi-wafers for high voltage power switches.

A leading GaN power device company, Transphorm, explained their high-voltage GaN devices that are actually out there on the market. They showed glimpses of the hoped for bright future of GaN by stating that, at present, compared to silicon devices, GaN power devices can give lower cost at the same performance, or higher performance at same cost as silicon. With the future bringing lower costs with higher performance.

Participants also suggested to leverage the LED industry base, not just its technical capacity and knowledge, but also its hard-fought experiences. For example, during the ramp-up of LEDs there was a gap between the technical side and the business/investor side, that should be learnt from, and avoided, when ramping up other GaN applications.

Even in a tough market like LEDs, you might expect the focus in China to be on low cost, however there are various companies in China actively researching and adding value, like nano materials, to their products, and succeeding in the markets.

~Next Generation Power Devices - GaN Vs SiC~The so-called, next-generation semiconductors, with large band gaps, have been pursued as they can offer lower power losses than present silicon power devices, and subsequently reduce system size and cost as less cooling systems and components are required.

Silicon Carbide (SiC) research started earlier, so it is about 10 years ahead of GaN developments, and SiC devices are starting to appear in the market, from leaders like Cree, as well as showing up in my Mitsubishi air-conditioner and in industrial systems.

Many material and performance issues had to be overcome to get devices to market, and the issue of high cost compared to silicon devices is still a barrier to widespread use. The expectation being that GaN devices will become lower cost than SiC, but SiC will likely hold its own for devices over 1000 volts. While both devices will have to try and sell themselves on the lower ‘total system and life-time costs'.

Japan has had extensive national R&D programs with industry for SiC, so companies like Rohm, as well as the vertically integrated companies like Mitsubishi Electric and Fuji Electric, have started ramping SiC devices in the past 1-2 years.

Korea has also set up a SiC consortium, however, with a focus on the materials and wafer value chain, it seems weak in power device companies.

In China, there are some companies like TankeBlue Semiconductor, who actually have a SiC wafer facility in Suzhou, and Tianyu Semiconductor doing SiC epiwafers. However China is less along the development and quality pathway in SiC, so maybe there is a window to jump straight to the GaN opportunity. However there are other issues, such as do Chinese companies have the expertise to design the power electronics and systems, especially high voltage (>600, 1000 Volts)? Or, if they can make low-cost and smaller systems, will Chinese companies try to open up the large market at low voltage (< 200 Volts) to GaN power devices? The Taiwanese inverter and power system companies in China, may be key to such system know-how and their uptake.

Seeing the energy in Suzhou and new ventures with confidence going after these GaN opportunities, they may just catch the GaN wave as it takes off.